Middle school EC’s will not be considered so TA should not be listed.
What about the University of the Pacific, not exactly in the Bay Area but much closer than UC Merced. If you are ELC (Top 9% at your HS or State), then UC Merced would be the default campus for admission if you are not accepted into your choice UC. It saves you $70 on the application fee if you meet the ELC threshold.
Also be aware that the Cal states/UC’s only use 10-11th in their GPA calculation. The UC’s consider your UW UC GPA, Capped weighted UC GPA and Fully weighted UC GPA. Cal states only consider your Capped weight UC/CSU GPA.
Here is the calculator which can use at the end of Junior year. No decision if the CSU’s and UC’s will be test optional, test blind or require test scores for the next admission cycle but other schools may require the SAT or ACT.
https://rogerhub.com/gpa-calculator-uc/
What is your HS course rigor and your intended major?
Unless the schools you apply give instructions in determining your Weighted GPA, like the CSU’s/UC’s, you should target schools where your Unweighted GPA makes your competitive.
Best of luck.